San Angelo , Texas -LRB- CNN -RRB- -- The Texas jury that found polygamist sect leader Warren Jeffs guilty Thursday of sexual assault will deliberate again to determine his punishment .

Jeffs , who represented himself after firing his defense team , remained stoic as the verdict was read .

Jurors will decide his fate after hearing additional witness testimony in the penalty phase of the trial , which began Thursday evening and will continue Friday .

The sect leader faces a maximum sentence of life in prison for his conviction of sexually assaulting a 12-year-old and a 15-year-old who were his `` spiritual wives . '' The jury convicted him of two counts of sexual assault on a child -- charges that stemmed from a 2008 raid on a ranch his church operates near Eldorado , Texas .

Texas Attorney General Greg Abbott hailed the verdict and said prosecutors were seeking a life sentence for Jeffs .

`` Here in the state of Texas , juries render tough , swift justice against anyone who would sexually assault a child , '' he said .

Before the verdict , witnesses showed jurors DNA evidence they said showed Jeffs conceived a baby with a 15-year-old child . And prosecutors presented an audio recording that they alleged documents Jeffs ' sexual assault of a 12-year-old girl in the presence of three other `` wives . ''

Abbott said attorneys were presenting new , `` repulsive '' evidence about the sect leader during the trial 's penalty phase .

`` I think it will confirm in -LRB- jurors ' -RRB- minds why they convicted the man and why they want to put him behind bars for a long time , '' he said .

Court adjourned about two hours after jurors reached a verdict Thursday . The trial was scheduled to continue at 10 a.m. Friday -LRB- 11 a.m. ET -RRB- .

Jurors deliberated for three hours and 45 minutes , starting Thursday afternoon . They sent out two notes during deliberations , requesting a CD player to listen to audio recordings and asking for the transcript of testimony from a witness .

Jeffs stood silently for most of his 30-minute closing argument Thursday -- the latest dramatic twist in a trial that included frequent objections and sermonlike speeches about religious freedom .

Jeffs stared at the table in front of him for most of his allotted block of time during closing arguments , as Judge Barbara Walther counted down .

He looked up at the jury when he reached the 20-minute mark , staring at each member . The jurors stared back .

Five minutes later , Jeffs mumbled , `` I am at peace . ''

The leader of the Fundamentalist Church of Jesus Christ of Latter-day Saints spoke so quietly that people in the courtroom strained to hear him .

Prosecutor Eric Nichols warned jurors not to be swayed by Jeffs ' frequent invocations of religious freedom as a defense .

The case , he said , has nothing to do with an attack on religion . Instead , it is about Jeffs and his actions , Nichols argued .

He showed pictures of Jeffs ' alleged victims as he summed up his argument .

Jeffs began the hearing on Thursday -- the fifth day of his trial -- by asking for what he called constitutional protection because he represents a religious organization . The judge immediately denied his request .

The sect leader then questioned witness J.D. Roundy , a sect member who also had taken the stand for four hours the day before . He did not call additional witnesses to the stand .

On Wednesday , Texas prosecutors rested their case after playing a key piece of evidence for jurors : a 20-minute audio tape that began and ended with a man saying prayer . Prosecutors alleged that the recording documents Jeffs ' sexual assault of a then-12-year-old girl in the presence of three other `` wives . ''

The girl had grown up in Jeffs ' Yearning for Zion ranch , clearing cactus and attending a Fundamentalist Church of Jesus Christ of Latter-day Saints school where Jeffs was principal , authorities said .

Prosecutors showed the jury a photo of her with her arms around Jeffs , and a marriage certificate which listed the girl 's age as 12 at the time .

On Tuesday , the jury heard audio recordings that prosecutors said showed Jeffs instructing a 14-year-old and his other young `` wives '' on how to sexually please him in order to win God 's favor .

Prosecutors said the 14-year-old was Jeffs ' `` spiritual wife '' and conceived a child with Jeffs when she was 15 .

Jeffs ' trial started last week . He made no plea during his arraignment and remained silent for more than a day of the trial proceedings . But on Friday , he began repeatedly objecting -- at one point delivering an hourlong speech about his religious freedom `` being trampled upon . ''

Jeffs could be sentenced to five years to life in prison on the charge of aggravated sexual assault regarding the alleged 12-year-old . For the other count , he would face a sentence of two to 20 years .

Jeffs ' breakaway sect is believed to have about 10,000 followers . Their practice of polygamy , which the mainstream Mormon Church renounced more than a century ago , is part of the sect 's doctrine .

The Texas legal proceedings began after about 400 children were taken from the sect 's Yearning for Zion ranch in 2008 . Jeffs was also charged with bigamy after the raid and is expected to be tried on that charge later .

Child protection officials said they found a `` pervasive pattern '' of sexual abuse on the ranch through forced marriages between underage girls and older men .

But the Texas Supreme Court ruled the state had no right to remove the children . The court also said the state lacked evidence to show that the children faced imminent danger of abuse . Most of the children were returned to their families , although some men at the ranch were charged with sexual abuse .

Jeffs was on the FBI 's 10 Most Wanted list when he was arrested five years ago during a routine 2006 traffic stop in Las Vegas .

He was convicted in Utah on two counts of being an accomplice to rape for using his religious influence over his followers to coerce a 14-year-old girl into marrying her 19-year-old cousin . Afterward , he was sentenced to two consecutive prison terms of five years to life .

But in July 2010 , the Utah Supreme Court overturned his convictions , ruling that the jury instructions were erroneous . Utah Attorney General Mark Shurtleff said last week Utah is prepared to retry Jeffs , depending on the outcome of the Texas case .

In Session 's Christi Paul , Jim Kyle , Grace Wong and Keith Lovely Jr. contributed to this report .

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NEW : The penalty phase of the trial will continue Friday

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The Texas attorney general says prosecutors are seeking a life sentence

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`` I am at peace , '' Warren Jeffs mumbles during closing arguments

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Prosecutors : recording played for jurors documents sexual assault of a child